ABSTRACT
Background
Functional impairments are a necessary requirement for the diagnosis of a dementia along with observed cognitive impairment. Comparatively, functional abilities are often relatively intact in those with mild cognitive impairment (MCI).
Objective
The current research examined the associations between memory clinic participants classified as cognitively intact, amnestic MCI, and mixed/dysexecutive MCI, using Jak-Bondi criteria, and Instrumental Activities of Daily Living - Compensation Scale (IADL-C) abilities, an informant-based questionnaire that quantifies functional abilities. The associations between functional abilities as assessed with the IADL-C and performance on neuropsychological tests were also investigated.
Methods
IADLC scores were obtained along with a comprehensive neuropsychological protocol on memory clinic participants (n = 100) classified as cognitively normal (CN), amnestic MCI (aMCI), or a combined mixed/dysexecutive (mixed/dys) MCI. Regression analyses were employed to determine how the IADLC related to neuropsychological test performance.
Results
On the IADLC, greater functional impairment was commonly observed in the mixed/dys MCI group compared to CN participants. Furthermore, the mixed/dys MCI group had lower scores on activities such as Money and Self-Management, Travel and Event Memory subscales compared to the CN group. Linear regression analyses found greater functional impairment in relation to lower scores on executive and episodic memory tests.
Conclusions
Greater functional impairment as assessed with the IADL-C appears to be disproportionately associated with dysexecutive difficulty, and to a lesser degree, episodic memory.
Disclosure statement
Drs. Libon and Swenson consult with Linus Health. Dr. Libon receives royalties from Linus Health. Drs. Libon and Swenson receive royalties from Oxford University Press.